Geared architecture gas turbine engine with planetary gear oil scavenge

ABSTRACT

A fan drive gear system for a turbofan engine according to an exemplary embodiment of this disclosure, among other possible things includes a sun gear that is rotatable about an axis, a plurality of intermediate gears driven by the sun gear, and a baffle that is disposed between at least two of the plurality of intermediate gears for defining a lubricant flow path from an interface between the sun gear and at least one of the plurality of intermediate gears. The baffle includes a channel with at least one ramp portion directing lubricant.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.62/962,470 which was filed on Jan. 17, 2020, and is incorporated hereinby reference.

BACKGROUND

A gas turbine engine typically includes a fan section, a compressorsection, a combustor section and a turbine section. Air entering thecompressor section is compressed and delivered into the combustionsection where it is mixed with fuel and ignited to generate a high-speedexhaust gas flow. The high-speed exhaust gas flow expands through theturbine section to drive the compressor and the fan section. Thecompressor section typically includes low and high pressure compressors,and the turbine section includes low and high pressure turbines.

A speed reduction device such as an epicyclical gear assembly may beutilized to drive the fan section such that the fan section may rotateat a speed different than the turbine section to increase overallpropulsive efficiency of the engine. Lubricant flow through anepicyclical gear assembly is gathered and directed to a sump and/orauxiliary lubrication system. Efficient direction of oil through thegear assembly increases operational efficiencies.

Turbine engine manufacturers continue to seek further improvements toengine performance including improvements to thermal, transfer andpropulsive efficiencies.

SUMMARY

A fan drive gear system for a turbofan engine according to an exemplaryembodiment of this disclosure, among other possible things includes asun gear that is rotatable about an axis, a plurality of intermediategears driven by the sun gear, and a baffle that is disposed between atleast two of the plurality of intermediate gears for defining alubricant flow path from an interface between the sun gear and at leastone of the plurality of intermediate gears. The baffle includes achannel with at least one ramp portion directing lubricant.

In a further embodiment of the foregoing fan drive gear system, the atleast one ram portion directs lubricant forward.

In a further embodiment of the foregoing fan drive gear system, the atleast one ramp portion directs lubricant aft.

In a further embodiment of the foregoing fan drive gear system, the atleast two ramp portions include a first ramp portion that directslubricant forward and a second ramp portion that directs lubricant aft.

In a further embodiment of any of the foregoing fan drive gear systems,the system includes a carrier that supports the intermediate gears and aring gear that circumscribes the intermediate gears. The baffle isattached to the carrier and the carrier rotates about the axis.

In a further embodiment of any of the foregoing fan drive gear systems,the system includes a forward gutter forward of the carrier and an aftgutter aft of the carrier. The first ramp portion directs lubricanttoward the forward gutter and the second ramp directs lubricant towardthe aft gutter.

In a further embodiment of any of the foregoing fan drive gear systems,the baffle includes an inlet opening into the channel. The inlet isdisposed radially inward of the first ramp portion and the second rampportion.

In a further embodiment of any of the foregoing fan drive gear systems,the baffle includes an apex between the first ramp portion and thesecond ramp portion. The apex is disposed at a midpoint of an axialwidth of the channel to direct equal amounts of lubricant forward andaft.

In a further embodiment of any of the foregoing fan drive gear systems,the baffle includes an apex between the first ramp portion and thesecond ramp portion. The apex is spaced apart from a midpoint of anaxial width of the channel to direct unequal amounts of lubricantforward and aft.

In a further embodiment of any of the foregoing fan drive gear systems,the apex is disposed at the inlet opening to the channel.

In a further embodiment of any of the foregoing fan drive gear systems,the apex is spaced aft of the midpoint of the axial width to direct morelubricant along the first ramp portion forward of the carrier than isdirected along the second ramp portion aft of the carrier.

In a further embodiment of any of the foregoing fan drive gear systems,the system includes a flow splitter that is disposed within the channelfor splitting lubricant between the first ramp portion and the secondramp portion. The flow splitter includes a splitter portion at the inletand a support portion that extends radially within the channel from thesplitter portion toward the first ramp portion and the second rampportion.

In a further embodiment of any of the foregoing fan drive gear systems,the flow splitter is spaced apart from a midway point of an axial widthof the channel such that incoming lubricant flow is unequallydistributed forward and aft of the baffle.

In a further embodiment of any of the foregoing fan drive gear systems,the baffle includes a wedge that extends into a circumferential cavitybetween oppositely facing helical gear regions of the sun gear.

A turbofan engine according to an exemplary embodiment of thisdisclosure, among other possible things includes a fan section that isrotatable about an axis, a core engine section that is disposed aboutthe axis, a primary lubrication system that includes a sump forgathering lubricant, an auxiliary lubrication system that is configuredto supply a lubricant flow in the absence of lubricant flow from theprimary lubricant system, and a fan drive gear system that is driven bythe core engine section for rotating the fan about the axis. The fandrive gear system includes a sun gear rotatable about an axis. The sungear includes a circumferential cavity that is disposed between a firstgear region and a second gear region. A plurality of intermediate gearsare driven by the sun gear. A baffle is disposed between at least two ofthe plurality of intermediate gears for defining a lubricant flow pathfrom an interface between the sun gear and at least one of the pluralityof intermediate gears. The baffle includes a channel with a first rampportion that directs lubricant to the auxiliary lubrication system and asecond ramp portion that directs lubricant toward the sump.

In a further embodiment of the foregoing turbofan engine, the engineincludes a carrier that supports the intermediate gears and a ring gearthat circumscribes the intermediate gears. The baffle is attached to thecarrier and the carrier rotates about the axis.

In a further embodiment of any of the foregoing turbofan engines, theengine includes a forward gutter forward of the carrier and an aftgutter aft of the carrier. The first ramp portion directs lubricanttoward the forward gutter and the second ramp directs lubricant towardthe aft gutter and the forward gutter directs lubricant flow to theauxiliary lubrication system and the aft gutter directs lubricant flowto the sump.

In a further embodiment of any of the foregoing turbofan engines, thebaffle directs more lubricant flow to the forward gutter and theauxiliary lubrication system than lubricant flow directed to the aftgutter and the sump.

In a further embodiment of any of the foregoing turbofan engines, anapex between the first ramp portion and the second ramp portion isdisposed at a midpoint of an axial width to direct equal amounts oflubricant along the first ramp portion forward of the carrier and alongthe second ramp portion aft of the carrier.

In a further embodiment of any of the foregoing turbofan engines, theapex between the first ramp portion and the second ramp portion isspaced aft of a midpoint of an axial width to direct more lubricantalong the first ramp portion forward of the carrier than is directedalong the second ramp portion aft of the carrier.

In a further embodiment of any of the foregoing turbofan engines, theengine includes a flow splitter that is disposed within the channel forsplitting lubricant between the first ramp portion and the second rampportion. The flow splitter includes a splitter portion at an inlet and asupport portion that extends radially within the channel from thesplitter portion toward the first ramp portion and the second rampportion.

In a further embodiment of any of the foregoing turbofan engines, theflow splitter is spaced apart from a midway point of an axial width ofthe channel such that incoming lubricant flow is unequally distributedforward and aft of the baffle.

In a further embodiment of any of the foregoing turbofan engines, thebaffle includes a wedge that extends into a circumferential cavitybetween oppositely facing helical gear regions of the sun gear.

Although the different examples have the specific components shown inthe illustrations, embodiments of this invention are not limited tothose particular combinations. It is possible to use some of thecomponents features from one of the several examples in alternatecombinations with features from one or more of each of the examples toprovide additional combinations.

These and other features disclosed herein can be best understood fromthe following specification and drawings, the following of which is abrief description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an example gas turbine engine.

FIG. 2 is a schematic view of an example fan drive gear system for a gasturbine engine.

FIG. 3 is a schematic view of an example geared architecture.

FIG. 4 is a schematic view of a portion of a geared architecture.

FIG. 5 is a perspective view of an example baffle.

FIG. 6 is a partial sectional view of the example baffle.

FIG. 7 is a side view of the example baffle.

FIG. 8 is a partial sectional view of another example baffle.

FIG. 9 is a partial sectional view of yet another example baffle.

FIG. 10 is a perspective view of another example baffle.

FIG. 11 is a partial sectional view of the example baffle of FIG. 10.

FIG. 12 is a side view of the example baffle of FIG. 10.

FIG. 13 is a partial sectional view of yet another example baffle.

DETAILED DESCRIPTION

FIG. 1 schematically illustrates a gas turbine engine 20. The gasturbine engine 20 is disclosed herein as a two-spool turbofan thatgenerally incorporates a fan section 22, a compressor section 24, acombustor section 26 and a turbine section 28. The fan section 22 drivesair along a bypass flow path B in a bypass duct defined within a housing18 such as a fan case or nacelle, and also drives air along a core flowpath C for compression and communication into the combustor section 26then expansion through the turbine section 28. Although depicted as atwo-spool turbofan gas turbine engine in the disclosed non-limitingembodiment, it should be understood that the concepts described hereinare not limited to use with two-spool turbofans as the teachings may beapplied to other types of turbine engines including three-spoolarchitectures.

The exemplary engine 20 generally includes a low speed spool 30 and ahigh speed spool 32 mounted for rotation about an engine centrallongitudinal axis A relative to an engine static structure 36 viaseveral bearing systems 38. It should be understood that additionalbearing systems 38 may be provided, and that the location of the bearingsystems 38 may be varied as appropriate to the application.

The low speed spool 30 generally includes an inner shaft 40 thatinterconnects, a first (or low) pressure compressor 44 and a first (orlow) pressure turbine 46. The inner shaft 40 is connected to the fansection 22 through a speed change mechanism, which in exemplary gasturbine engine 20 is illustrated as a geared architecture 48 to drivethe fan section 22 at a lower speed than the low speed spool 30. Thehigh speed spool 32 includes an outer shaft 50 that interconnects asecond (or high) pressure compressor 52 and a second (or high) pressureturbine 54. A combustor 56 is arranged in exemplary gas turbine 20between the high pressure compressor 52 and the high pressure turbine54. A mid-turbine frame 58 of the engine static structure 36 may bearranged generally between the high pressure turbine 54 and the lowpressure turbine 46. The mid-turbine frame 58 further supports bearingsystems 38 in the turbine section 28. The inner shaft 40 and the outershaft 50 are concentric and rotate via bearing systems 38 about theengine central longitudinal axis A which is collinear with theirlongitudinal axes.

The core airflow is compressed by the low pressure compressor 44 thenthe high pressure compressor 52, mixed and burned with fuel in thecombustor 56, then expanded through the high pressure turbine 54 and lowpressure turbine 46. The mid-turbine frame 58 includes airfoils 60 whichare in the core airflow path C. The turbines 46, 54 rotationally drivethe respective low speed spool 30 and high speed spool 32 in response tothe expansion. It will be appreciated that each of the positions of thefan section 22, compressor section 24, combustor section 26, turbinesection 28, and geared architecture 48 may be varied. For example, thegeared architecture 48 may be located aft of the low pressurecompressor, or aft of the combustor section 26 or even aft of turbinesection 28, and fan 42 may be positioned forward or aft of the locationof geared architecture 48.

The engine 20 in one example is a high-bypass geared aircraft engine. Ina further example, the engine 20 bypass ratio is greater than about six(6), with an example embodiment being greater than about ten (10), thegeared architecture 48 is an epicyclic gear train, such as a planetarygear system or other gear system, with a gear reduction ratio of greaterthan about 2.3 and the low pressure turbine 46 has a pressure ratio thatis greater than about five. In one disclosed embodiment, the engine 20bypass ratio is greater than about ten (10:1), the fan diameter issignificantly larger than that of the low pressure compressor 44, andthe low pressure turbine 46 has a pressure ratio that is greater thanabout five 5:1. Low pressure turbine 46 pressure ratio is pressuremeasured prior to inlet of low pressure turbine 46 as related to thepressure at the outlet of the low pressure turbine 46 prior to anexhaust nozzle. The geared architecture 48 may be an epicycle geartrain, such as a planetary gear system or other gear system, with a gearreduction ratio of greater than about 2.3:1 and less than about 5:1. Itshould be understood, however, that the above parameters are onlyexemplary of one embodiment of a geared architecture engine and that thepresent invention is applicable to other gas turbine engines includingdirect drive turbofans.

A significant amount of thrust is provided by the bypass flow B due tothe high bypass ratio. The fan section 22 of the engine 20 is designedfor a particular flight condition—typically cruise at about 0.8 Mach andabout 35,000 feet (10,668 meters). The flight condition of 0.8 Mach and35,000 ft (10,668 meters), with the engine at its best fuelconsumption—also known as “bucket cruise Thrust Specific FuelConsumption (′TSFC)”—is the industry standard parameter of lbm of fuelbeing burned divided by lbf of thrust the engine produces at thatminimum point. “Low fan pressure ratio” is the pressure ratio across thefan blade alone, without a Fan Exit Guide Vane (“FEGV”) system. The lowfan pressure ratio as disclosed herein according to one non-limitingembodiment is less than about 1.45. “Low corrected fan tip speed” is theactual fan tip speed in ft/sec divided by an industry standardtemperature correction of [(Tram ° R)/(518.7° R)]^(0.5). The “Lowcorrected fan tip speed” as disclosed herein according to onenon-limiting embodiment is less than about 1150 ft/second (350.5meters/second).

The example gas turbine engine includes the fan section 22 thatcomprises in one non-limiting embodiment less than about 26 fan blades42. In another non-limiting embodiment, the fan section 22 includes lessthan about 20 fan blades 42. Moreover, in one disclosed embodiment thelow pressure turbine 46 includes no more than about 6 turbine rotorsschematically indicated at 34. In another non-limiting exampleembodiment, the low pressure turbine 46 includes about 3 turbine rotors.A ratio between the number of fan blades 42 and the number of lowpressure turbine rotors is between about 3.3 and about 8.6. The examplelow pressure turbine 46 provides the driving power to rotate the fansection 22 and therefore the relationship between the number of turbinerotors 34 in the low pressure turbine 46 and the number of blades 42 inthe fan section 22 disclose an example gas turbine engine 20 withincreased power transfer efficiency.

The engine 20 includes a lubrication system 62 that provides lubricantto the geared architecture 48, the various bearing systems 38 as well asany other components that require lubricant flow. The lubrication system62 includes a primary lubrication system 66 that normally provideslubricant to the geared architecture 48. The lubrication system 62further includes an auxiliary lubrication system 64 that provideslubricant flow during conditions where the primary lubrication system 66may not provide a desired amount of lubricant flow. Lubricant from theauxiliary lubrication system 64, the geared architecture 48 and thebearing systems 38 is eventually recovered in a sump 68 forrecirculation by the primary lubrication system 66.

Referring to FIGS. 2, 3 and 4 with continued reference to FIG. 1, thegeared architecture 48 is part of a fan drive gear system 55 that drivesthe fan 22. Lubricant within the geared architecture 48 is directed intogear mesh interfaces 90 and then guided out by baffles 80. From thebaffles 80 lubricant is directed to either the auxiliary lubricationsystem 62 or the back to the sump of the primary lubrication system. Thebaffles 80 provide a flow split of lubricant expelled from the gearsystem 48 to prevent overflow of lubricant flow to the auxiliary system64 and thereby reduce some of the windage and churning losses thatreduce gear efficiency. The baffles are further provided to directexhaust lubrication flow through and away from the geared architecturewith minimal windage and churning losses.

The example geared architecture 48 includes a sun gear 72 that drivesand is in meshed engagement with a plurality of intermediate gears 74.The intermediate gears 74 are often referred to as either star gears orplanet gears. Star gears rotate about fixed axes, whereas planet gearsare supported on axes that rotate about the sun gear 72. In thisexample, the intermediate gears 74 are referred to as planet gears 74and are supported by a carrier assembly 76. The carrier assembly 76 andthe planet gears 74 rotate about the axis A to drive a fan drive shaft45. A ring gear 78 circumscribes the plurality of planet gears 74 and isin meshing engagement with each of the planet gears 74. The ring gear 78is fixed to a portion of the engine static structure 36. A baffle 80 isdisposed between each of the planet gears 74 proximate the meshingengagement 90 with the sun gear 72.

The example sun gear 72 includes a circumferential cavity 92 between twogear portions 94. The baffle 80 includes a scoop 118 that extends intothe circumferential cavity 92. The baffle 80 is secured to inner sidesof the carrier 76 proximate the gear mesh interface 90 between theplanet gears 74 and the sun gear 72. In one example embodiment, the gearportions 94 are opposing helical gears. However, other gearconfigurations are within the scope and contemplation of thisdisclosure.

Rotation of the carrier 76 generates centrifugal forces that drivelubricant exiting the geared architecture 48 radially outward away fromaxis A. The centrifugal forces are utilized to drive a first portion ofexhausted lubricant 70 through passages 88 to the sump 68. Lubricant inthe sump 68 is recirculated back to the primary lubrication system 66.

A second portion of exhausted lubricant 75 is directed into passages 86to the auxiliary lubrication system 64. The baffle 80 directs the firstportion of the exhausted lubricant flow 70 axially aft into an aftgutter 84 and the second portion of the exhausted lubricant flow 75axially forward into a forward gutter 82. The forward gutter 82 capturesthe exhausted lubricant 75 and directs it into passages 86 to theauxiliary lubrication system 64. The aft gutter 84 captures exhaustedlubricant 70 and directs the lubricant through passages 88 into the sump68. The relative positions of the auxiliary lubrication system 64 andthe sump 68 are an example embodiment and other relative positions ofauxiliary lubrication system 64 and the sump could be utilized and arewithin the scope and contemplation of this disclosure. For example, theforward gutter 82 may direct the exhausted lubricant axially forward tothe sump 68, and the aft gutter 84 may direct the exhausted lubricantaft to the auxiliary lubrication system 64.

The terms axial, radial, forward and aft are utilized throughout thisdisclosure to denote relative positon of components. The term axialrefers to a direction that is substantially parallel to the enginelongitudinal axis A. The term radial refers to a direction that issubstantially transverse to the engine longitudinal axis. The termforward generally is used to describe a position or direction that istoward the fan section 22 of the engine 20. Similarly, the term aft isgenerally used to describe a position or direction that is toward theturbine section 28 of the engine 20.

In one disclosed embodiment, the second portion of the lubricant flow 75directed to the auxiliary lubrication system 64 is more than the firstportion of lubricant flow 70 directed toward the sump. Accordingly, thefirst portion of lubricant flow 70 is not equal to the second portion oflubricant flow 75. The baffle 80 controls the split of lubricant flow70, 75 forward and aft of the geared architecture 48. Excess flowdirected to the auxiliary lubrication system 64 can create windage andchurning losses that can reduce overall gearbox operating efficiencies.Further, the shape and position of the baffle 80 can create windage andchurning losses reducing gearbox efficiency.

The baffle 80 includes features for proportioning exhaust lubricantflows 70, 75 to maintain a supply in the auxiliary lubrication system 64without providing excess flow or generating windage or churning losses.In one disclosed embodiment, approximately 80% of lubricant exhaustedfrom the geared architecture 48 is routed to the auxiliary lubricationsystem 64 by the baffle 80. In another disclosed embodiment, more than50% of lubricant exhausted from the geared architecture 48 is routed tothe auxiliary lubrication system 64 by the baffle 80. In anotherdisclosed embodiment, lubricant flow is split evenly between theauxiliary system 64 and the sump 68. Additionally, it is also within thecontemplation of this disclosure to direct all lubricant flow eitherforward or aft to one of the auxiliary lubrication system 64 and thesump 68.

Referring to FIGS. 5, 6, and 7 with continued reference to FIG. 2, theexample baffle 80 includes a channel 96 defined between an outer wall112 and a back wall 106. FIG. 6 illustrates the example baffle 80 withthe outer wall 112 removed to show the ramp portions 108 and 110 withinchannel 96. The channel 96 extends radially outward from an inlet 98 toa forward end 95 on a forward side 83 of the baffle 80 and to an aft end97 on an aft side 85 of the baffle 80. The channel 96 includes a firstramp portion 108 that directs lubricant from the inlet 98 toward theforward end 95. A second ramp portion 110 directs lubricant flow towardthe aft end 97. The first ramp portion 108 and the second ramp portion110 meet at an apex 116 near the inlet 98. The apex 116 splits lubricantflow entering the inlet 98 such that it flows toward one of the forwardend 95 and the aft end 97 of the channel 96.

The baffle 80 includes a width 100 between a forward side 83 and an aftside 85. The scoop 118 is disposed at a midpoint 102 equally spacedbetween the sides 83, 85. The apex 116 is spaced apart from the midpoint102 a distance 104 such that it is offset from the midpoint 102. In onedisclosed embodiment, the distance 104 extends aft from the midpoint102. The location of the apex 116 defines and proportions the amount oflubricant that is routed to each of the forward and aft ends 95, 97. Inthis disclosed embodiment, the location of the apex 116 offset towardthe aft side 85 to provide more lubricant flow forward along the firstramp portion 108. As appreciated, the apex 116 location may be adjustedto tailor a desired split of exhausted lubricant forward and aft of thegeared architecture.

The first and second ramp portions 108, 110 extend across the entirechannel 96 between the outer wall 112 and the back wall 106. The firstramp portion 108 and the second ramp portion 110 are disposed near theinlet to minimize directional changes in lubricant flow. Directionalchanges in lubricant flow impart work on the lubricant flow that cancreate windage and churning, and heat the lubricant.

The outer wall 112 is curved to correspond with a curvature of thecorresponding planet gear 74. The channel 96 includes a curvature thatcorresponds to the outer wall 112 and the planet gear 74. It should beappreciated, that other curvatures and shapes could be utilized toprovide a desired lubricant flow and are within the scope andcontemplation of this disclosure. The example baffle 80 is disclosed asa single integral part, but may be fabricated and formed in severaldifferent parts.

Referring to FIG. 8, another example baffle 150 is shown with the outerwall 112 removed to show another example ramp portion 152 within achannel 155. The channel 155 has a height 105 and a width 100. The rampportion 152 begins at the inlet 98 and extends to the forward end 95 todirect all lubricant toward the forward end 95. The ramp portion 152 isa continuous surface that extends the full width 100 of the baffle 150from an aft most point 154 at the inlet 98 to a forward most point 156that is radially outward of the inlet 98. In this example, the aft mostpoint 154 is also the apex of the ramp portion 152. An angle 158 of theramp portion 152 from a line radial plane extending from the enginelongitudinal axis A is dependent on the width 100 and the radial height105 of the channel 155. In one example embodiment, the angle 158 isbetween about 30° and 60°. In another disclosed embodiment, the angle158 is about 45°.

Referring to FIG. 9, another example baffle 160 is shown with the outerwall 112 removed to show example ramp portions 162A and 162B within achannel 165. The ramp portions 162A and 162B begin at an apex 164 at theinlet 98 and diverge to opposite sides of the baffle 160. The apex 164is positioned at the midpoint 102 of the width 100 such that lubricantflow is directed evenly toward the forward point 168 and an aft point166. An angle 170 between the ramp portions 162A and 162B is dependenton the width 100 baffle and the radial height 105 of the channel 165. Inone disclosed embodiment, the angle 170 is between 45° and 75°. Inanother disclosed embodiment, the angle 170 is about 60°.

Referring to FIGS. 10, 11, and 12, another example baffle 120 is shownand includes a flow splitter 124 dividing exhausted lubricant flow. FIG.11 is shown without a forward wall 128 to show the flow splitter 124more clearly. The flow splitter 124 extends radially upward from a scoop122 through inlet 126 and into a channel 130. The flow splitter 124includes a splitter portion 136 and a support portion 134. The splitterportion 136 directs flow toward the forward side 144 and aft toward theaft side 146 of the baffle 120. The example flow splitter 124 isdisposed at a midpoint 138 of a width 140 of the baffle 120 andtherefore evenly splits lubricant flow toward forward side 144 and anaft side 146.

The baffle 120 includes a forward wall 128 and a back wall 132. Thechannel 130 is defined between the forward and back walls 128, 132. Theforward wall 128 may be partially supported by the support portion 134of the flow splitter 124. The support portion 134 extends from the backwall 132 to the forward wall 128. The support portion 134 may be anintegral portion of the baffle 120 and define a rib that providessupport for the forward wall 128.

Referring to FIG. 13, another disclosed baffle 125 includes a flowsplitter 150 that is spaced a distance 142 apart from the midpoint 138.FIG. 13 is shown without the forward wall to enable a clear view of theflow splitter 150. The spaced distance 142 from the midpoint 138provides for an unequal split in lubricant flow between the forward side144 and the aft side 146. In one disclosed embodiment, the location ofthe splitter 150 provides 80% of exhausted lubricant flow toward theforward side with the remainder of lubricant low being directed aft. Inanother embodiment, the flow splitter 150 is disposed to provide morethan 50% of lubricant flow forward and less than 50% aft. It should beappreciated, that the location of the flow splitter 150 may be arrangedto proportion exhausted lubricant flow as desired for a specificapplication and such other positons are within the contemplation andscope of this disclosure.

The disclosed baffles provide for the distribution of exhaust lubricantflow between forward and aft sides of the geared architecture.Distribution of the exhaust lubricant flows are proportioned toefficiently allocate lubricant flow between the auxiliary lubricationsystem and the sump of the primary lubrication system.

Although example embodiments have been described, a worker of ordinaryskill in this art would recognize that certain modifications would comewithin the scope of this disclosure. For that reason, the followingclaims should be studied to determine the scope and content of thisdisclosure.

What is claimed is:
 1. A fan drive gear system for a turbofan enginecomprising: a sun gear rotatable about an axis; a plurality ofintermediate gears driven by the sun gear; and a baffle disposed betweenat least two of the plurality of intermediate gears for defining alubricant flow path from an interface between the sun gear and at leastone of the plurality of intermediate gears, the baffle including achannel with a first ramp portion and a second ramp portion configuredfor directing lubricant and a flow splitter disposed within the channelfor splitting lubricant between the first ramp portion and the secondramp portion, wherein the flow splitter is spaced apart from a midwaypoint of an axial width of the channel such that incoming lubricant flowis unequally distributed forward and aft of the baffle.
 2. The fan drivegear system as recited in claim 1, wherein the first ramp portiondirects lubricant forward and the second ramp portion directs lubricantaft.
 3. The fan drive gear system as recited in claim 2, including acarrier supporting the intermediate gears and a ring gear circumscribingthe intermediate gears, wherein the baffle is attached to the carrierand the carrier rotates about the axis.
 4. The fan drive gear system asrecited in claim 3, including a forward gutter forward of the carrierand an aft gutter aft of the carrier, wherein the first ramp portiondirects lubricant toward the forward gutter and the second ramp portiondirects lubricant toward the aft gutter.
 5. The fan drive gear system asrecited in claim 4, wherein the baffle includes an inlet opening intothe channel, the inlet disposed radially inward of the first rampportion and the second ramp portion.
 6. The fan drive gear system asrecited in claim 5, wherein the flow splitter includes a splitterportion at the inlet and a support portion extending radially within thechannel from the splitter portion toward the first ramp portion and thesecond ramp portion.
 7. The fan drive gear system as recited in claim 1,wherein the baffle includes a wedge extending into a circumferentialcavity between oppositely facing helical gear regions of the sun gear.8. A turbofan engine comprising: a fan section rotatable about an axis;a core engine section disposed about the axis; a primary lubricationsystem including a sump for gathering lubricant; an auxiliarylubrication system configured to supply a lubricant flow in an absenceof a lubricant flow from the primary lubricant system; a fan drive gearsystem driven by the core engine section for rotating fan of the fansection about the axis, the fan drive gear system including: a sun gearrotatable about the axis, the sun gear including a circumferentialcavity disposed between a first gear region and a second gear region; aplurality of intermediate gears driven by the sun gear; a baffledisposed between at least two of the plurality of intermediate gears fordefining a lubricant flow path from an interface between the sun gearand at least one of the plurality of intermediate gears, the baffleincluding a channel with a first ramp portion directing lubricant to theauxiliary lubrication system, a second ramp portion directing lubricanttoward the sump and a flow splitter disposed within the channel forsplitting lubricant between the first ramp portion and the second rampportion, wherein the flow splitter is spaced apart from a midway pointof an axial width of the channel such that incoming lubricant flow isunequally distributed between the auxiliary lubrication system and thesump.
 9. The turbofan engine as recited in claim 8, including a carriersupporting the intermediate gears and a ring gear circumscribing theintermediate gears, wherein the baffle is attached to the carrier andthe carrier rotates about the axis.
 10. The turbofan engine as recitedin claim 9, including a forward gutter forward of the carrier and an aftgutter aft of the carrier, wherein the first ramp portion directslubricant toward the forward gutter and the second ramp portion directslubricant toward the aft gutter and the forward gutter directs lubricantto the auxiliary lubrication system and the aft gutter directs lubricantto the sump.
 11. The turbofan engine as recited in claim 10, wherein thebaffle directs more lubricant to the forward gutter and the auxiliarylubrication system than lubricant directed to the aft gutter and thesump.
 12. The turbofan engine as recited in claim 8, wherein the baffleincludes a wedge extending into the circumferential cavity.